Get rid of base::SharedMemory::NULLHandle();

base/memory/shared_memory_win.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/memory/shared_memory.h"
 
 #include <aclapi.h>
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 153 matching lines @@
   Unmap();
   Close();
 }
 
 // static
 bool SharedMemory::IsHandleValid(const SharedMemoryHandle& handle) {
   return handle.IsValid();
 }
 
 // static
-SharedMemoryHandle SharedMemory::NULLHandle() {
-  return SharedMemoryHandle();
-}
-
-// static
 void SharedMemory::CloseHandle(const SharedMemoryHandle& handle) {
   handle.Close();
 }
 
 // static
 size_t SharedMemory::GetHandleLimit() {
   // Rounded down from value reported here:
   // http://blogs.technet.com/b/markrussinovich/archive/2009/09/29/3283844.aspx
   return static_cast<size_t>(1 << 23);
 }
@@ skipping 198 matching lines @@
 
 SharedMemoryHandle SharedMemory::TakeHandle() {
   SharedMemoryHandle handle(mapped_file_.Take(), base::GetCurrentProcId());
   handle.SetOwnershipPassesToIPC(true);
   memory_ = nullptr;
   mapped_size_ = 0;
   return handle;
 }
 
 }  // namespace base